Image-processing method and program for compound apparatus

ABSTRACT

There is described a compound apparatus, having a plurality of outputting functions including at least a copy function. The compound apparatus includes: an image-reading device to read an original image residing on a document so as to convert the original image into image data; a binary-coded image data generating section to generate binary-coded image data by applying a binary-coding processing to the image data; an image-data storing section to store the image data or the binary-coded image data; a designating section to designate an outputting function among the plurality of outputting functions; a resolution setting section to set an output-image resolution, based on an output resolution of the outputting function; and a resolution converting section to convert a resolution of either the image data or the binary-coded image data, stored in the image-data storing section, to the output-image resolution set by the resolution setting section.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a compound apparatus havingvarious functions, in which at least a copy function is included.

[0002] Conventionally, there has been well-known a compound apparatushaving two or more specific functions among data accessing functions,such as image-outputting functions including a copying function, aprinting function, a facsimile transmitting function, etc., andimage-inputting functions, such as a scanner function, etc. According tosuch the compound apparatus, it has been possible to output an originalimage, which was read by using, for instance, the scanner function, byemploying a desired outputting function selected from the copyingfunction, the printing function and the facsimile transmitting function.

[0003] Conventionally, however, since output resolutions correspondingto the functions provided with the compound apparatus, such as thecopying function, the printing function and the facsimile transmittingfunction, are generally different relative to each other, the originalimage should be read again corresponding to the resolution for thefunction currently employed, even if the same original image havealready read for another function.

SUMMARY OF THE INVENTION

[0004] To overcome the abovementioned drawbacks in conventional compoundapparatus, it is an object of the present invention to provide acompound apparatus, which makes it possible to alleviate processingburdens when outputting the same original image from outputtingfunctions being different each other.

[0005] Accordingly, to overcome the cited shortcomings, theabovementioned object of the present invention can be attained bycompound apparatus, an image-processing method and a program describedas follow.

[0006] (1) A compound apparatus, having a plurality of outputtingfunctions including at least a copy function, comprising: animage-reading device to read an original image residing on a document soas to convert the original image into image data thereof; a binary-codedimage data generating section to generate binary-coded image data byapplying a binary-coding processing to the image data read from theoriginal image; an image-data storing section to store the image data,read from the original image, or the binary-coded image data, generatedby the binary-coded image data generating section, therein; adesignating section to designate an outputting function among theplurality of outputting functions; a resolution setting section to setan output-image resolution, based on an output resolution of theoutputting function designated by the designating section; and aresolution converting section to convert a resolution of either theimage data or the binary-coded image data, stored in the image-datastoring section, to the output-image resolution set by the resolutionsetting section.

[0007] (2) The compound apparatus of item 1, further comprising: aresolution selecting section to select a specific output resolution outof a plurality of output resolutions established in advance; wherein theresolution converting section converts a resolution of either the imagedata or the binary-coded image data, stored in the image-data storingsection, to the specific output resolution selected by the resolutionselecting section, instead of the output resolution set by theresolution setting section.

[0008] (3) The compound apparatus of item 1, wherein, based on a ratioof the resolution of either the image data or the binary-coded imagedata and the output-image resolution set by the resolution settingsection, the resolution converting section divides either the image dataor the binary-coded image data into a plurality of pixel blocks, andthen, applies a binary-coding processing to each of the plurality ofpixel blocks so as to convert a resolution of either the image data orthe binary-coded image data to the output-image resolution set by theresolution setting section.

[0009] (4) The compound apparatus of item 2, wherein, based on a ratioof the resolution of either the image data or the binary-coded imagedata and the specific output resolution selected by the resolutionselecting section, the resolution converting section divides either theimage data or the binary-coded image data into a plurality of pixelblocks, and then, applies a binary-coding processing to each of theplurality of pixel blocks so as to convert a resolution of either theimage data or the binary-coded image data to the specific outputresolution selected by the resolution selecting section.

[0010] (5) The compound apparatus of item 3, wherein the resolutionconverting section comprises a binary-coding reference value settingsection to set a binary-coding reference value employed for thebinary-coding processing.

[0011] (6) The compound apparatus of item 5, wherein the binary-codingreference value setting section establishes the binary-coding referencevalue, corresponding to the output-image resolution set by theresolution setting section.

[0012] (7) The compound apparatus of item 5, wherein the image-readingdevice comprises a reading mode selecting section to select a readingmode out of a plurality of reading modes provided in advance,corresponding to at least either a variable density image or abinary-coded image, and performs an image-reading operation based on thereading mode selected by the reading mode selecting section; and whereinthe binary-coding reference value setting section establishes thebinary-coding reference value, corresponding to the reading modeselected by the reading mode selecting section.

[0013] (8) The compound apparatus of item 5, further comprising anoutput-density setting section to set an output density of theoutputting function designated by the designating section; wherein abinary-coding reference value setting section sets a binary-codingreference value, corresponding to the output density set by theoutput-density setting section.

[0014] (9) The compound apparatus of item 1, wherein the resolutionconverting section employs an error diffusion method for converting theresolution of either the image data or the binary-coded image data tothe output-image resolution.

[0015] (10) The compound apparatus of item 9, wherein the resolutionconverting section selects the error diffusion method to be employed,corresponding to the output-image resolution and a reading mode, out ofplural kinds of error diffusion methods provided in advance.

[0016] (11) An image-processing method, performed in a compoundapparatus having a plurality of outputting functions including at leasta copy function, comprising the steps of: reading an original imageresiding on a document so as to convert the original image into imagedata thereof; generating binary-coded image data by applying abinary-coding processing to the image data read from the original image;storing the image data, read from the original image, or thebinary-coded image data, generated from the original image, in animage-data storing section; designating an outputting function among theplurality of outputting functions provided in the compound apparatus;setting an output-image resolution, based on an output resolution of theoutputting function designated in the designating step; and converting aresolution of either the image data or the binary-coded image data,stored in the image-data storing section, to the output-image resolutionset in the setting step.

[0017] (12) A program for conducting an image-processing method, to beexecuted in a compound apparatus having a plurality of outputtingfunctions including at least a copy function, the image-processingmethod comprising the steps of: reading an original image residing on adocument so as to convert the original image into image data thereof;generating binary-coded image data by applying a binary-codingprocessing to the image data read from the original image; storing theimage data, read from the original image, or the binary-coded imagedata, generated from the original image, in an image-data storingsection; designating an outputting function among the plurality ofoutputting functions provided in the compound apparatus; setting anoutput-image resolution, based on an output resolution of the outputtingfunction designated in the designating step; and converting a resolutionof either the image data or the binary-coded image data, stored in theimage-data storing section, to the output-image resolution set in thesetting step.

[0018] Further, to overcome the abovementioned problems, other compoundapparatus, another image-processing method and another program, embodiedin the present invention, will be described as follow:

[0019] (13) A compound apparatus, which has a plurality of functionsincluding at least a copy function, characterized by comprising:

[0020] image-reading means for reading an original image;

[0021] binary-coded image generating means for generating binary-codedimage by binary-coding the read image;

[0022] image storing means for storing the binary-coded image or theread image read from the original image;

[0023] designating means for designating a function as a outputtingfunction among the plurality of functions;

[0024] resolution setting means for setting an output-image resolution,based on a resolution of the outputting function designated by thedesignating means; and

[0025] resolution converting means for converting a resolution of theimage stored in the image storing means, to the output-image resolutionset by the resolution setting means.

[0026] (14) An image-processing method in a compound apparatus having aplurality of functions including at least a copy function, characterizedby comprising the processes of:

[0027] a image-reading process for reading an original image;

[0028] a binary-coded image generating process for generatingbinary-coded image by binary-coding the read image;

[0029] an image storing process for storing the binary-coded image orthe read image read from the original image;

[0030] a designating process for designating a function as a outputtingfunction among the plurality of functions, including the copy function,provided in the compound apparatus;

[0031] a resolution setting process for setting an output-imageresolution, based on a resolution of the outputting function designatedby the designating means; and

[0032] a resolution converting process for converting a resolution ofthe image stored in the image storing means, to the output-imageresolution set by the resolution setting means.

[0033] (15) A program, with respect to a compound apparatus having aplurality of functions including at least a copy function, for realizingthe functions of:

[0034] a image-reading function for reading an original image;

[0035] a binary-coded image generating function for generatingbinary-coded image by binary-coding the read image;

[0036] an image storing function for storing the binary-coded image orthe read image read from the original image;

[0037] a designating function for designating a function as a outputtingfunction among the plurality of functions;

[0038] a resolution setting function for setting an output-imageresolution, based on a resolution of the outputting function designatedby the designating means; and

[0039] a resolution converting function for converting a resolution ofthe image stored in the image storing means, to the output-imageresolution set by the resolution setting means.

[0040] According to the present invention, the image data, read from thedocument, or the binary-coded image data, generated by binary-coding theimage data, are stored in the image-data storing section. Then, theresolution of the binary-coded image data are converted on the basis ofthe resolution of the selected outputting function. Therefore, when thesame original image is outputted by plural outputting functionscorresponding to different output resolutions, it becomes possible toomit the processes of rereading the original image to cope with each ofthe outputting functions.

[0041] (16) The compound apparatus, described in item 13, characterizedby further comprising:

[0042] resolution selecting means for selecting an output resolution,and characterized in that

[0043] the resolution converting means sets the output resolution,selected by the resolution selecting means, as an output-imageresolution, instead the resolution of the designated output function.

[0044] According to the present invention, it becomes possible not onlyto output the original image in a desired resolution, but also to outputplural images having resolutions different each other from the sameoriginal image, without rereading the original image for everyresolution.

[0045] (17) The compound apparatus, described in item 13 or 16,characterized in that,

[0046] based on a ratio of the resolution of the image stored in theimage storing means and the output-image resolution set by theresolution setting means, the resolution converting means converts theresolution of the image to the output-image resolution by dividing theimage into a plurality of pixel blocks and binary-coding each block.

[0047] According to the present invention, since the resolution of thebinary-coded image data is converted to the output-image resolution onthe basis of the resolution-converting ratio calculated from the ratioof the resolution of the binary-coded image data and output-imageresolution, it becomes possible to output the image, in which featuresof the original image are little deteriorated.

[0048] (18) The compound apparatus, described in item 17, characterizedin that,

[0049] the resolution converting means provided with a binary-codingreference value setting means for setting a binary-coding referencevalue employed for the binary-coding processing.

[0050] According to the present invention, it is possible to vary thereference value when binary-coding the block. Therefore, it is possibleto output the image while varying the characteristics of the originalimage. For instance, by varying the density as a reference value, thevariable-density of the whole image can be changed.

[0051] (19) The compound apparatus, described in item 18, characterizedin that,

[0052] the binary-coding reference value setting means establishes thereference value, corresponding to the output-image resolution set by theresolution setting means.

[0053] According to the present invention, it becomes possible to setthe reference value by the output-image resolution when binary-codingthe block.

[0054] (20) The compound apparatus, described in item 18, characterizedin that,

[0055] the image-reading means provided with reading mode selectingmeans for selecting a reading mode being selectable corresponding to atleast either a variable density image or a binary-coded image, andperforms an image-reading operation based on the reading mode selected,and the reference value setting means establishes the reference value,corresponding to the reading mode selected.

[0056] According to the present invention, it is possible to establishthe reference value employed for binary-coding the block, correspondingto the reading mode. Accordingly, it becomes possible to vary thereference value, corresponding to the characteristics of the image.

[0057] (21) The compound apparatus, described in item 18, characterizedby further comprising,

[0058] output-density setting means for setting an output density of theoutputting function designated by the designating means; andcharacterized in that,

[0059] the binary-coding reference value setting means sets a referencevalue, corresponding to the output density set by the output-densitysetting means.

[0060] According to the present invention, it becomes possible not onlyto output an image having a desired density from the original image, butalso to output plural types of images, having output densities beingdifferent each other, without repeating the rereading operations forevery image.

[0061] (22) The compound apparatus, described in anyone of items 13-21,characterized in that,

[0062] the resolution converting means employs an error diffusion methodfor converting the resolution of the image to the output-imageresolution.

[0063] According to the present invention, it becomes possible toreflect inclination of the block, which would disappear when theresolution of the binary-coded image data is converted to theoutput-image resolution, onto the other blocks residing in the peripheryof the block. Therefore, it is possible to perform the resolutionconversion processing with little deteriorating the density distributionin the output image, resulting in an improvement of the quality of theoutput image.

[0064] (23) The compound apparatus, described in item 22, characterizedin that,

[0065] the resolution converting means selects the error diffusionmethod to be employed, corresponding to the output-image resolution anda reading mode, out of plural kinds of error diffusion methods.

[0066] According to the present invention, it becomes possible to varythe output image, by changing the error diffusion method to be employedfor binary-coding the blocks corresponding to the output-imageresolution and the reading mode.

BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Other objects and advantages of the present invention will becomeapparent upon reading the following detailed description and uponreference to the drawings in which:

[0068]FIG. 1 shows an example of a functional block diagram of acompound apparatus embodied in the present invention;

[0069]FIG. 2 shows a flowchart of exemplified operations performed in acompound apparatus embodied in the present invention;

[0070]FIG. 3 shows an example of table of reference values;

[0071]FIG. 4 shows an example of the resolutions each of whichcorresponds to each of inputting/outputting functions of a compoundapparatus embodied in the present invention;

[0072]FIG. 5 shows an explanatory schematic diagram for explaining theprocess of the resolution converting operation;

[0073]FIG. 6 shows a flowchart of exemplified operations of the errordiffusion method performed by the CPU; and

[0074]FIG. 7 shows an explanatory drawing for explaining the errordiffusion method employed in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0075] Referring to the drawings, the compound apparatus, embodied inthe present invention, will be detailed in the following. Incidentally,although the compound apparatus (the compound image-forming apparatus)having three outputting functions of the copying function, the printingfunction and the facsimile transmitting function is exemplified as anexample apparatus embodied in the present invention, the scope of thepresent invention is not limited to the exemplified compound apparatus.

[0076] In the compound apparatus embodied in the present invention, thedevice having the scanner function reads the original image to store itsbinary-coded image data or the image data as they are in it, and whenoutputting the original image in a mode of the outputting functionselected from the copying function, the printing function and thefacsimile transmitting function, the resolution of the stored originalimage is converted to another resolution corresponding to the selectedoutputting function.

[0077]FIG. 1 shows an example of the functional block diagram ofcompound apparatus 10 embodied in the present invention. As shown inFIG. 1, compound apparatus 10 comprises CPU (Central Processing Unit)100, image-reading device 200, operating section 300, displaying section400, transmitting section 500, printing device 600, ROM (Read OnlyMemory) 700 and RAM (Random Access Memory) 800.

[0078] CPU 100 controls each of functional sections constitutingcompound apparatus 10, overall operations of compound apparatus 10, etc.Concretely speaking, CPU 100 performs various processing operationsbased on various kinds of controlling programs and data stored in ROM700, etc. with respect to the operations to be performed in eachsection, or based on the information transferred from other functionalsections constituting compound apparatus 10, and controls the operationsof compound apparatus 10 by outputting command signals to the functionalsection concerned.

[0079] Further, CPU 100 conducts various kinds of functions embodied inthe present invention. Especially, hereinafter, a functional section forgenerating binary-coded image data and another functional section forconverting an input resolution of read image data to an outputresolution of outputted image data are referred to as binary-coded imagedata generating section 120 and resolution converting section 140,respectively.

[0080] Image-reading device 200 comprises, for instance, a light source,CCD (Charge Coupled Device), etc., so as to read the original image byoptically scanning a photographic image or a document to detect lightreflected or transmitted from/through it, and then, by converting thedetected signals to digital image data.

[0081] Operating section 300 is provided with, for instance, variouskinds of operating buttons, to each of which an individual function isallotted, and outputs status signals, indicating the pushed button,etc., to CPU 100. The user of compound apparatus 10 inputs an operationcommand by pushing the operating button concerned. The changeover ofoutputting functions, such as “copier”, “printer” and “facsimile”, theselection of a reading mode when reading the document, the designationof output density of the image when outputting the image, thedesignation of output resolution of the image when outputting the image,the designation of a number of sheets or a dialing operation of afacsimile number, the start command for outputting copies or a facsimiletransmission, or the halt command for outputting copies or a facsimiletransmission can be achieved by operation the operating buttons equippedin operating section 300. Incidentally, it is also possible to designcompound apparatus 10 so that the abovementioned inputting operationscan be achieved by selecting one of areas displayed on displayingsection 400 detailed later.

[0082] Displaying section 400 serves as a notifying means for notifyingthe user of various kinds of messages including a message for urging theuser to conduct the inputting operation for compound apparatus 10. Thedisplayed information are renewed in response to the inputting operationachieved by pushing the operating buttons as mentioned in the above.Further, displaying section 400 comprises a liquid-crystal display, etc.CPU 100 outputs display signals, corresponding to the message to bedisplayed, to displaying section 400, and controls displaying section400 so as to display the message on it.

[0083] Transmitting section 500 comprises a MODEM(Modulator/Demodulator) or a TA (Terminal Adaptor), etc., and CPU 100conducts controlling operations for communicating with externalapparatuses on the network, such as an Internet, LAN, WAN, etc., throughtransmitting section 500 and the communication lines, such as, telephonelines, ISDN lines, wireless communication lines, exclusive communicationlines, CATV lines, etc. Further, transmitting section 500 conductsbilateral facsimile transmissions in accordance with the G3 (Group 3)standard or the G4 (Group 4) standard, etc.

[0084] Under the controlling actions conducted by CPU 100, printingdevice 600 prints the image on a sheet-type recording medium, based onthe image data read as a printing object or the other data received fromthe external apparatus through transmitting section 500, whileconducting the conveying operation of the sheet-type recording medium.

[0085] An initializing program for conducting various kinds of initialsetting operations, for inspecting hardware or for loading necessaryprograms is stored in ROM 700. CPU 100 executes the initializing programwhen the power of compound apparatus 10 is turned ON, so as toinitialize the operating environment of compound apparatus 10.

[0086] Further, various kinds of controlling programs pertaining to theoperations in each of the sections constituting compound apparatus 10 orthe other programs for conducting various kinds of functions provided incompound apparatus 10 are stored in ROM 700. Still further, in order toconduct the functions embodied in the present invention, “Table ofReference Values”, detailed later, is also stored in ROM 700.

[0087] RAM 800 is provided with a storing region in which various kindsof programs to be executed by CPU 100 and the data pertaining to thoseprograms are temporarily stored. Further, in order to conduct thefunctions embodied in the present invention, RAM 800 is also providedwith read image data storing region 820 for storing the image datadirectly read by image-reading device 200, binary-coded image datastoring region 840 for storing the binary-coded image data generated bybinary-coding the image data directly read by image-reading device 200and output image data storing region 860 for storing the output imagedata whose resolution is converted from that of the binary-coded imagedata, based on the output resolution required for the selectedoutputting function.

[0088] Referring to the flowchart shown in FIG. 2, the operations ofcompound apparatus 10, having the configuration mentioned in the above,will be detailed in the following.

[0089] As shown in FIG. 2, initially, CPU 100 accepts various kinds ofinputting operations, such as a selection of the desired functionperformed by the user, an inputting operation of setting items, etc.,(step 10). For instance, various kinds of inputting operations can beconducted by means of the push buttons arranged on the operation paneldisposed at an arbitral position over compound apparatus 10, the buttonsor icons displayed on the displaying screen, etc.

[0090] In step 10, CPU 100 waits for the selecting operation of theoutput function and the inputting operation of the selected mode forreading the original image.

[0091] Incidentally, the mode for reading the original image can beselected from four modes of “character/photograph mode”, “charactermode”, “photograph mode” and “pencil mode”, and an appropriate mode isselected corresponding to the features and structures of the originalimage. The case, in which “facsimile” (namely, facsimile transmission)is selected as the outputting function and “character mode” is selectedas the mode for reading the original image, will be detailed in thefollowing.

[0092] When CPU 100 accepts the selecting operation of the outputtingfunction and the reading mode, CPU 100 controls operations performed inimage-reading device 200 so as to read the original image in accordancewith the selected reading mode (step 12). In addition, at the same time,CPU 100 revises read image data storing region 820 with the image dataread from the original image.

[0093] Then, binary-coded image data generating section 120 generatesbinary-coded image data from the image data read from the original image(step 14).

[0094] Concretely speaking, binary-coded image data generating section120 analyzes information of each of dots included in the image data readfrom the original image, and then, performs the processing operation forgenerating binary-coded image data in which the dot informationconcerned are converted to bit information. In other words, binary-codedimage data generating section 120 generates the binary-coded image datain such a manner that a certain dot information, having a density levelhigher than the reference density level established in advance, is setat “1”, while a certain dot information, having a density level lowerthan the reference density level, is set at “0”. Further, at this time,binary-coded image data generating section 120 revises binary-codedimage data storing region 840 with the binary-coded image data generatedin the above process.

[0095] Next, CPU 100 establishes the reference value to be employed whenconducting the resolution converting processing, detailed later, (step16). Concretely speaking, CPU 100 establishes the reference value inaccordance with the selected reading mode, while referring to table ofreference values 720.

[0096]FIG. 3 shows an example of table of reference values 720. As shownin FIG. 3, table of reference values 720 is a kind of data table inwhich each of the modes of “character/photograph mode”, “charactermode”, “photograph mode” and “pencil mode” is correlated with each ofthe reference values (%). Accordingly, in step 16, referring to table ofreference values 720, CPU 100 establishes the reference value utilizedfor the resolution converting processing, detailed later, at thereference value of 80%, which is stored at a position correlated withthe reading mode of “character mode”.

[0097] Successively, CPU 100 establishes the output resolution of theoutput image in accordance with the resolution corresponding to theselected outputting function (step 18). FIG. 4 shows an example of theresolutions each of which corresponds to each of inputting function andoutputting functions. As shown in FIG. 4, in the example embodied in thepresent invention, the input resolution corresponding to the inputtingfunction of “scanner” is 600×600 dpi, and for instance, the outputresolution corresponding to the outputting function of “copier” is300×200 dpi. In other words, CPU 100 establishes the output resolutionof 200×100 dpi, corresponding to the outputting function of “facsimile”selected by the user, as a resolution of the output image in step 18.

[0098] Then, resolution converting section 140 performs the resolutionconverting operation for converting the current resolution of thebinary-coded image data to the output resolution established by CPU 100(step 18). Referring to FIG. 5, the resolution converting operation willbe detailed in the following. Incidentally, FIG. 5 shows explanatoryschematic diagram for explaining the process of the resolutionconverting operation.

[0099] Initially, resolution converting section 140 calculates a numberof pixels to be included in one block, based on the ratio of theresolution of the binary-coded image data read from the original image(namely, the input resolution corresponding to the inputting function of“scanner”) and the output resolution established by CPU 100.Successively, resolution converting section 140 divides the binary-codedimage data into blocks each of which includes the calculated number ofpixels, as shown in FIG. 5.

[0100] Concretely speaking, since the input resolution of inputtingfunction of “scanner” is 600×600 dpi and the output resolution of theoutputting function of “facsimile” is 200×100 dpi, the binary-codedimage data are divided into blocks each of which includes 3×6 pixels asa unit block.

[0101] Successively, resolution converting section 140 applies thebinary-coding processing to each of the blocks divided. Concretelyspeaking, resolution converting section 140 calculates a ratio betweennumbers of black pixels and the total pixels included in the blockconcerned. For instance, since a number of the black pixels is 8 pixelsof 16 total pixels in the block having a pixel pattern as shown insection (b) of FIG. 5, resolution converting section 140 calculates aratio of black pixels as being 50%.

[0102] Further, resolution converting section 140 compares thecalculated ratio of black pixels, included in the block concerned, withthe reference value established in step 16, so as to establish “0” (inthis case, indicating a white pixel) to the pixel data equivalent to theblock concerned when determining that the calculated ratio of blackpixels does not exceed the reference value, or to establish “1” (in thiscase, indicating a black pixel) to the pixel data equivalent to theblock concerned when determining that the calculated ratio of blackpixels exceeds the reference value. Accordingly, since the referencevalue is established at 80% in step 16, resolution converting section140 sets the pixel data, equivalent to the block concerned, at white(“0”), as shown in section (c) of FIG. 5.

[0103] By repeating the abovementioned processing, the output imagedata, having the output resolution converted from the input resolutionof the binary-coded image data, can be generated. In addition, at thistime, resolution converting section 140 revises output image datastoring region 860 with the output image data generated by theabovementioned process.

[0104] When the resolution converting operation for the binary-codedimage data concerned is completed, CPU 100 controls the functionalsection with respect to the selected outputting function so as to outputthe image based on the output image data (step 22). Accordingly, theoutput image data concerned are transmitted via facsimile.

[0105] Incidentally, when, for instance, the “photograph mode” isselected as the mode for reading the original image, it is alsoapplicable that the error-diffusion method is employed for binary-codingoperation in the resolution converting processing mentioned in theabove. FIG. 6 shows a flowchart of operations performed in resolutionconverting section 140, when the “photograph mode” is selected as themode for reading the original image.

[0106] As shown in FIG. 6, resolution converting section 140 calculatesa number of pixels to be included in one block, based on the ratio ofthe resolution of the binary-coded image data read from the originalimage and the output resolution established by CPU 100. Successively,resolution converting section 140 divides the binary-coded image datainto blocks each of which includes the calculated number of pixels.Then, resolution converting section 140 calculates a sum of the blackpixels included in one block and the diffusion errors established in amanner detailed later. Further, resolution converting section 140compares the calculated sum value with the reference value (step S30),so as to establish “1” to the pixel data equivalent to the blockconcerned when determining that the calculated sum value exceeds thereference value (step S32).

[0107] Successively, resolution converting section 140 establishes anumber of white pixels (namely, a number of pixels to be converted toblack pixels), among the total number of pixels included in the blockconcerned, into error information (step S34).

[0108] Further, in step S30, resolution converting section 140establishes “0” to the pixel data equivalent to the block concerned whendetermining that the calculated sum value does not exceed the referencevalue (step S36).

[0109] Successively, resolution converting section 140 establishes anumber of black pixels (namely, a number of pixels to be converted towhite pixels), among the total number of pixels included in the blockconcerned, into error information (step S38).

[0110] When the error information is established in step S34 or stepS38, resolution converting section 140 calculates diffusion errors (stepS40).

[0111] Now, referring to FIG. 7, the error diffusion method will bedetailed in the following. In FIG. 7, each of rectangular areasindicates each of pixels of the output image data (namely, each ofblocks in the binary-coded image data). The pixels residing aboveborderline BL are already converted pixels, pixel P10 filed with blackcolor is a currently referred objective-pixel for conversion processingand other pixels are to be referred later.

[0112] Concretely speaking, according to the error diffusion methodapplied to pixel P10, being an objective-pixel for conversionprocessing, shown in FIG. 7, values, into which the error informationcalculated in step S34 or step S38 is equally divided, are allotted topixels P20, P21, P22, P23, which are located in the vicinity of thecurrent objective-pixel for conversion processing and to be referredlater. For instance, if the error information is four, resolutionconverting section 140 allots +1 to each of pixels P20, P21, P22, P23,being unreferred pixels. The allotted diffusion error information aretemporarily stored in, for instance, RAM 800, and resolution convertingsection 140 determines the conversion objective pixel information,referring to the diffusion error concerned. Incidentally, the scope ofthe error diffusion method is not limited to the abovementioned method.It is also applicable that one of the various kinds of diffusingmethods, such as the method in which errors are diffused to theunreferred pixels located in a region narrower than that of theabovementioned example, the method in which errors are diffused to theunreferred pixels distributing in a wide region, is selected as needed.

[0113] As described in the above referring to FIG. 7, resolutionconverting section 140 revises the error information of the unreferredpixels concerned, after calculating the diffusion errors to be set forthe unreferred pixels adjacent to the position of the currentobjective-pixel for conversion processing in the output image data (stepS42).

[0114] According to the compound apparatus as described in theforegoing, by storing the binary-coded image data of the original image,it becomes possible to output the original image through each of variouskinds of outputting functions whose resolutions are different relativeto each other, without rereading the original image corresponding toeach of the outputting resolutions. Therefore, when the same originalimage is outputted by plural outputting functions corresponding todifferent output resolutions, it becomes possible to omit the processesof rereading the original image to cope with each of the outputtingfunctions.

[0115] Concretely speaking, for instance, in case that the originalimage, which is already transmitted via facsimile, is also outputted viacopy function, only by selecting the outputting function of “copy”, itis possible to convert the resolution of the stored binary-coded imagedata to the output resolution corresponding to the outputting functionof “copy” so as to output the copy of the original image withoutrereading the original image.

[0116] Incidentally, the scope of the present invention is not limitedto the compound apparatus, embodied in the present invention, describedin the foregoing. The disclosed embodiment can be adaptively modified bya skilled person without departing from the spirit and scope of theinvention.

[0117] For instance, although binary-coded image data generating section120 converts the read image into the binary-coded image data, which arefurther processed in the later stages, in the compound apparatusembodied in the present invention, it is also applicable that themultiple-valued data are processed in the later stages as they arewithout performing the binary-coding processing in binary-coded imagedata generating section 120. In this case, however, it is necessary suchthe processing that resolution converting section 140 calculates anaverage value of gradation data of the pixels included in each block,and “1” (namely, a black color, in this case) is established when thecalculated average value is equal to or greater than a predeterminedthreshold level, while “0” (namely, a white color, in this case) isestablished when the calculated average value is smaller than thepredetermined threshold level.

[0118] Further, it is also applicable such a configuration that theresolution of the output image is designated and inputted into compoundapparatus 10 via a manual operation. For instance, an operationinputting means, such as a push button, etc., corresponding to theresolution-setting processing of the output image, is provided so thatthe resolution of the output image can be inputted via the operationinputting means. CPU 100 conducts the resolution-converting processingon the basis of the output resolution inputted via the operationinputting means when converting the binary-coded data to the outputimage data.

[0119] Still further, it is also applicable such a configuration thatthe density of the output image is designated and inputted into compoundapparatus 10 via a manual operation. For instance, an operationinputting means, such as a push button, etc., corresponding to thedensity-setting processing of the output image, is provided so that thedensity of the output image can be inputted via the operation inputtingmeans. CPU 100 establishes the binary-coding reference value employedfor the resolution-converting processing on the basis of the outputdensity inputted via the operation inputting means.

[0120] According to the abovementioned configuration, even when pluraltypes of images, having output resolutions and/or output densities beingdifferent relative to each other, are outputted from the same originalimage, it is possible to outputs such the different plural types ofimages, having desired output resolutions and/or desired outputdensities, without repeating the rereading operations for every image.

[0121] As described in the foregoing, according to the presentinvention, the following effects can be attained.

[0122] (1) In a compound apparatus embodied in the present invention,the image data, read from the document, or the binary-coded image data,generated by binary-coding the image data, are stored in the image-datastoring section. Then, the resolution of the binary-coded image data areconverted on the basis of the resolution of the selected outputtingfunction. Therefore, when the same original image is outputted by pluraloutputting functions corresponding to different output resolutions, itbecomes possible to omit the processes of rereading the original imageto cope with each of the outputting functions.

[0123] (2) It becomes possible not only to output the original image ina desired resolution, but also to output plural images havingresolutions different each other from the same original image, withoutrereading the original image for every resolution.

[0124] (3) Since the resolution of the binary-coded image data isconverted to the output-image resolution on the basis of theresolution-converting ratio calculated from the ratio of the resolutionof the binary-coded image data and output-image resolution, it becomespossible to output the image, in which features of the original imageare little deteriorated.

[0125] (4) It is possible to vary the reference value when binary-codingthe block. Therefore, it is possible to output the image while varyingthe characteristics of the original image. For instance, by varying thedensity as a reference value, the variable-density of the whole imagecan be changed.

[0126] (5) It becomes possible to set the reference value by theoutput-image resolution when binary-coding the block.

[0127] (6) It is possible to establish the reference value employed forbinary-coding the block, corresponding to the reading mode. Accordingly,it becomes possible to vary the reference value, corresponding to thecharacteristics of the image.

[0128] (7) It becomes possible not only to output an image having adesired density from the original image, but also to output plural typesof images, having output densities being different each other, withoutrepeating the rereading operations for every image.

[0129] (8) It becomes possible to reflect inclination of the block,which would disappear when the resolution of the binary-coded image datais converted to the output-image resolution, onto the other blocksresiding in the periphery of the block. Therefore, it is possible toperform the resolution conversion processing with little deterioratingthe density distribution in the output image, resulting in animprovement of the quality of the output image.

[0130] (9) It becomes possible to vary the output image, by changing theerror diffusion method to be employed for binary-coding the blockscorresponding to the output-image resolution and the reading mode.

[0131] Disclosed embodiment can be varied by a skilled person withoutdeparting from the spirit and scope of the invention.

What is claimed is:
 1. A compound apparatus, having a plurality ofoutputting functions including at least a copy function, comprising: animage-reading device to read an original image residing on a document soas to convert said original image into image data thereof; abinary-coded image data generating section to generate binary-codedimage data by applying a binary-coding processing to said image dataread from said original image; an image-data storing section to storesaid image data, read from said original image, or said binary-codedimage data, generated by said binary-coded image data generatingsection, therein; a designating section to designate an outputtingfunction among said plurality of outputting functions; a resolutionsetting section to set an output-image resolution, based on an outputresolution of said outputting function designated by said designatingsection; and a resolution converting section to convert a resolution ofeither said image data or said binary-coded image data, stored in saidimage-data storing section, to said output-image resolution set by saidresolution setting section.
 2. The compound apparatus of claim 1,further comprising: a resolution selecting section to select a specificoutput resolution out of a plurality of output resolutions establishedin advance; wherein said resolution converting section converts aresolution of either said image data or said binary-coded image data,stored in said image-data storing section, to said specific outputresolution selected by said resolution selecting section, instead ofsaid output resolution set by said resolution setting section.
 3. Thecompound apparatus of claim 1, wherein, based on a ratio of saidresolution of either said image data or said binary-coded image data andsaid output-image resolution set by said resolution setting section,said resolution converting section divides either said image data orsaid binary-coded image data into a plurality of pixel blocks, and then,applies a binary-coding processing to each of said plurality of pixelblocks so as to convert a resolution of either said image data or saidbinary-coded image data to said output-image resolution set by saidresolution setting section.
 4. The compound apparatus of claim 2,wherein, based on a ratio of said resolution of either said image dataor said binary-coded image data and said specific output resolutionselected by said resolution selecting section, said resolutionconverting section divides either said image data or said binary-codedimage data into a plurality of pixel blocks, and then, applies abinary-coding processing to each of said plurality of pixel blocks so asto convert a resolution of either said image data or said binary-codedimage data to said specific output resolution selected by saidresolution selecting section.
 5. The compound apparatus of claim 3,wherein said resolution converting section comprises a binary-codingreference value setting section to set a binary-coding reference valueemployed for said binary-coding processing.
 6. The compound apparatus ofclaim 5, wherein said binary-coding reference value setting sectionestablishes said binary-coding reference value, corresponding to saidoutput-image resolution set by said resolution setting section.
 7. Thecompound apparatus of claim 5, wherein said image-reading devicecomprises a reading mode selecting section to select a reading mode outof a plurality of reading modes provided in advance, corresponding to atleast either a variable density image or a binary-coded image, andperforms an image-reading operation based on said reading mode selectedby said reading mode selecting section; and wherein said binary-codingreference value setting section establishes said binary-coding referencevalue, corresponding to said reading mode selected by said reading modeselecting section.
 8. The compound apparatus of claim 5, furthercomprising an output-density setting section to set an output density ofsaid outputting function designated by said designating section; whereina binary-coding reference value setting section sets a binary-codingreference value, corresponding to said output density set by saidoutput-density setting section.
 9. The compound apparatus of claim 1,wherein said resolution converting section employs an error diffusionmethod for converting said resolution of either said image data or saidbinary-coded image data to said output-image resolution.
 10. Thecompound apparatus of claim 9, wherein said resolution convertingsection selects said error diffusion method to be employed,corresponding to said output-image resolution and a reading mode, out ofplural kinds of error diffusion methods provided in advance.
 11. Animage-processing method, performed in a compound apparatus having aplurality of outputting functions including at least a copy function,comprising the steps of: reading an original image residing on adocument so as to convert said original image into image data thereof;generating binary-coded image data by applying a binary-codingprocessing to said image data read from said original image; storingsaid image data, read from said original image, or said binary-codedimage data, generated from said original image, in an image-data storingsection; designating an outputting function among said plurality ofoutputting functions provided in said compound apparatus; setting anoutput-image resolution, based on an output resolution of saidoutputting function designated in said designating step; and convertinga resolution of either said image data or said binary-coded image data,stored in said image-data storing section, to said output-imageresolution set in said setting step.
 12. A program for conducting animage-processing method, to be executed in a compound apparatus having aplurality of outputting functions including at least a copy function,said image-processing method comprising the steps of: reading anoriginal image residing on a document so as to convert said originalimage into image data thereof; generating binary-coded image data byapplying a binary-coding processing to said image data read from saidoriginal image; storing said image data, read from said original image,or said binary-coded image data, generated from said original image, inan image-data storing section; designating an outputting function amongsaid plurality of outputting functions provided in said compoundapparatus; setting an output-image resolution, based on an outputresolution of said outputting function designated in said designatedstep; and converting a resolution of either said image data or saidbinary-coded image data, stored in said image-data storing section, tosaid output-image resolution set in said setting step.